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The process of creating spin-polarized electrons has been studied for some time but continues to surprise physicists. These types of electrons have their spin aligned in a specific direction. The probability of creating a spin-polarized electron from an atom tends to be rather small except in some very specific situations. Yet, in a new paper published in Physical Review A, JILA graduate student Spencer Walker, former graduate student Joel Venzke, and former undergraduate student Lucas Kolanz in the Becker Lab theorized a new way towards enhancing this probability through the use of ultrashort laser pulses and an electron’s so-called doorway states. These doorway states are excited states of an electron in an atom that is closest to its lowest energy state, the ground state.

In a significant advance toward the future redefinition of the international unit of time, the second, a research team led by the National Institute of Standards and Technology (NIST) has compared three of the world’s leading atomic clocks with record accuracy over both air and optical fiber links.

In this work, we showed half-minute scale coherence in a tweezer clock of 150 atoms, demonstrated high relative stability, and established new methods for scaling ultracold arrays of neutral atoms. Congratulations to the team! See also: The Nature highlight on our work and the recent entangled optical clock paper from the Vuletić group; and, NIST highlight.

For the first time, researchers can turn on an electric field to manipulate molecular interactions, get them to cool down further, and start to explore collective physics where all molecules are coupled to each other.

Building on their newfound ability to induce molecules in ultracold gases to interact with each other over long distances, JILA researchers have used an electric “knob” to influence molecular collisions and dramatically raise or lower chemical reaction rates.

Margaret Murnane and Henry Kapteyn, who pioneered technologies for generating coherent X-rays, which helped propel research in dynamic processes in atoms, molecules and materials, have been named fellows of the National Academy of Inventors.

Older atomic clocks operating at microwave frequencies have hunted for dark matter before, but this is the first time a newer clock, operating at higher optical frequencies, and an ultra-stable oscillator to ensure steady light waves have been harnessed to set more precise bounds on the search.

JILA fellow Jun Ye has been named Highly Cited Researcher for 2020 by Clarivate Analytics. Ye has been awarded the Highly Cited Researcher in the field of physics every year since 2014.

Follow that electron! JILA researchers have proposed a means of capturing an electron's flight path during ionization, and in doing so, determining the state of the atom at that moment.

JILA has a new associate fellow. Meet Shuo Sun.